compact fluorescent

Spring is on the way for our friends down under. With that in mind [x2Jiggy] built this compact fluorescent grow lamp to help start the seeds for his garden. He used materials that are easy to find, and multiple bulbs means that you can mix and match their color warmth in order to get the wavelengths of light best for plant growth.

He started by building the box out of MDF. It is lined mostly with a reflector meant to go in your car’s windshield when you leave it in a hot parking lot. He sealed the seams of the reflector using what he calls flashing tape. This is the rubbery type of stuff used as soft flashing around windows.

The bulb sockets came from an old string of party lights. Wiring is run through plastic junction boxes which keeps the setup code-compliant. Each of the CFLs draw 20 Watts for a total consumption of 160 Watts. Combine this with a DIY hydroponic tent and you’ll be eating fresh greens year round.

If you’re going camping this summer, or just want a cheap emergency lantern powered by a pair of AA batteries, you probably can’t do much better than [rimstar]’s Joule thief compact florescent lantern.

The circuit for [rimstar]’s battery powered CFL bulb is a Joule thief. While these circuits are usually used as a demonstration to get every last bit of energy out of a battery with a LED, [rimstar] upgraded everything with a better transformer and a power transistor to light up a CFL bulb.

What’s really interesting about this build is it provides a use for blown compact fluorescent bulbs. The normal failure mode of these light bulbs is usually the electronics going bad, not the tube. By replacing the electronics with a homemade circuit, it’s an easy way to reuse these broken bulbs.

[Kizo] repurposed a flatbed scanner to use as an exposure box for making printed circuit boards. Exposure time is controlled by an AVR ATtiny2313 microcontroller. The device is connected to a separate display board to control four 7-segment displays using one shift register for each. Time is set in ten second increments and once started, switches on the lights with a relay. Once the right exposure time has been reached, the lights are switched off and a piezo speaker is buzzed. There’s no mention of they type of bulbs he’s using but they look like compact fluorescent with tin foil beneath as a reflector.